-LRB- CNN -RRB- -- If there 's one thing that kills bedroom coziness , home decorators say , it 's a bed-in-a-bag set .

It might seem like a smart idea to buy everything together , but ultra-coordinated , flat bedding and stiff comforters often found in bagged bedding are the enemy of an inviting bedroom , said Holly Browning , DIY blogger and former home accent and interior designer .

`` Fluff is key , like clouds or cotton , '' Browning said .

For her , and many decorators who contributed to this week 's `` inviting bedrooms '' Open House assignment , the feel of bedding is important . Whether it 's crisp , white sheets from a store like Target or expensive , vintage-looking throws from Anthropologie , decorators say it 's important to feel like you 're sleeping on a cloud .

And to get that feel , you must control the fluff . A carefully curated collection of down duvets , mattress pads , quilts and blankets of different thicknesses allow for temperature control and comfort , whether you 're fast asleep or sniffling through a miserable flu bug -- and that probably wo n't come from a preselected , oversized bag , decorators said .

But is it just decorator snobbery ?

When pressed , decor blogger Emily Clark said , `` A bed in a bag can sometimes be a good jumping-off point , if you add some other elements like patterned sheets or different shams . ''

Likewise , Browning relented : `` Well , it 's OK , really . If you are unsure of what pillows and bedding accessories you like , then buying a bag might be best . ''

But she also pointed out that the pillows in said bag are `` not always the softest material , '' and that matters a lot .

Pillows

Pillows are key , decorators said , and they must be chosen carefully .

`` Pillows have always been a big discussion in our house , '' said interior designer and The Little Black Door blogger Elizabeth Baumgartner . `` After a lot of trial and error , I 've found that we need at least one king-size synthetic pillow and one regular-size down pillow per person . '' The combination , she said , is perfection .

`` I think every bed needs several good pillows besides the decorative kind , '' said Clark . The calming , white master bedroom she decorated is `` the most comfortable place for me in our home , '' she said .

Julie Holloway , part of the Milk and Honey Home decorator team from Roswell , Georgia , also finds pillows paramount . `` My husband and I love our Tempur-Pedic pillows that mold to the shape of our neck and head , '' she said . `` Our young boys love them , too , and steal them often . ''

Furniture

But scratchy sheets aside , comforters that match throw pillows that match curtains , elicit a shudder and `` ugh '' from interior designers like Shannon Berrey . And what of a matched suite of bedroom furniture ? They inspired the same kind of disdain .

`` Do n't do it ! '' Berrey pleaded , urging a more eclectic approach .

The `` paint by numbers '' mountain vacation bedroom Berrey designed embodies her decorating aesthetic . `` Some vintage pieces , some new , different wood tones , some painted , '' is how she put together a cozy , inviting bedroom for clients .

Interior decorator and blogger Bethany Brower said matching bedroom furniture makes her feel `` claustrophobic . ''

`` Matching bedroom sets are definitely a buzzkill for me , '' Little House on the Update blogger Corrie Moore said . `` I feel like a bedroom can be uncomfortable if it 's too formal . ''

Headboards

And according to the logic of most bedroom decorating schemes , designers say the bed and headboard are more important than the rest of the furniture . `` A headboard gives the bed a presence in the room , '' Clark said . `` Whether it 's a full bed frame or even just a pretty quilt hanging on the wall behind the bed , a headboard makes the room feel more finished . ''

`` Important '' does n't always mean `` expensive . '' Many headboards featured in this week 's gallery are DIY projects .

`` This spot is so special to my husband and me because we built and upholstered the bed ourselves , '' Kelly Marzka said . `` Every night when we crawl in to sleep , we 're reminded of this project we took on , not knowing if we could even do it . ''

CNN iReport head-honcho and home decor blogger Katie Hawkins-Gaar is similarly proud of the impact her DIY headboard has on her master bedroom .

`` We have an Ikea Malm bed , something that was in our price range when we first bought it , but it never really stood out on its own , '' she said . `` After making a custom headboard , it 's like we have a brand new bed ! It gave our bedroom so much character and the fact that it 's handmade -- it was my husband 's first attempt at a project of that scale -- makes it so much more meaningful . ''

The large headboard Browning created for her master bedroom reflects her personal style .

`` Right now I am loving gray and silver . The corrugated steel roofing I used for this one is shiny and massive , '' she said . `` It 's not very feminine but it creates a soft , romantic reflection from the side lamps . ''

Lighting

Clark also finds that lamps are an indispensable ingredient to an inviting bedroom .

`` I recently moved the lamps in our bedroom to another room in the house , and we were with only an overhead light for a couple of months , '' she said . `` It just felt so cold to me . ''

Soft light makes a bedroom cozier , she said . So , too , can black-out drapes , or even eye masks and white noise machines . Light-limiting drapes can come in handy for the occasional sick day , Brower said .

`` There 's nothing worse than being laid up in bed with a cold and it 's sunny and wonderful just outside the window . I can pull my drapes shut and block out the sun and pretend I 'm not missing out on a glorious day , '' she said .

TVs

The only thing it seems decorators ca n't agree on when it comes to bedrooms is whether to put a TV in the room . For some , like Berrey , it 's a must .

`` I know for so many a TV in the bedroom is a big no-no , but I have to have a TV in the bedroom . I love to lay in bed and watch TV until I fall asleep . It 's really the only thing I need ; No scented sprays or the sounds of crashing waves , just the sounds of the ` Real Housewives , ' '' she said .

Even if they think TVs do n't belong in bedrooms , decorators confess to it apologetically .

`` I know I 'm in the minority , '' Baumgartner said , `` but no TV . ''

`` I 'll be hated for this one , '' said Holloway , who says TVs destroy the cozy vibe of a bedroom . `` Are we not bombarded by screens ? If you can swing it , no home office or TV in your bedroom . ''

Are you obsessed with decorating your house ? Show us your skills at CNN 's Open House and your photo could be featured in next week 's story . Our next focus : well-dressed mantels .

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Decorators : Bed-in-a-bag sets can be stiff and too coordinated for a cozy room .

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`` A bedroom can be uncomfortable if it 's too formal , '' blogger Corrie Moore said of furniture choices

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Share your gorgeous mantel photos and ideas on the next CNN Open House iReport assignment